Fuel injection systems that deliver fuel to fuel consuming devices, for example internal combustion engines, have been known for many years. The typical fuel injection system draws fuel from a fuel tank to a fuel rail mounted adjacent to the cylinder bank of the engine. The fuel injectors are electro-mechanical devices that deliver fuel in precise amounts and times to the respective cylinder.
While the engine is running, the valve within each fuel injector is constantly being operationally cycled from an open position to a closed position. Vibration is generated by the mechanical movement of the injector valve and pressure waves are generated by the movement of the fuel flowing through the injectors. Additionally, a substantial amount of heat generated in the combustion chambers of the cylinder heads may be transferred from the engine to the fuel injector. In order to minimize transfer of heat from the engine to the fuel injector and to prevent the transmission of vibration from the fuel injector, it is known to provide a fuel injector isolator. In one known arrangement as shown in FIG. 6, a fuel injector isolator 118 is provided for receiving a fuel injector 110 (only a portion of which is shown). Fuel injector isolator 118 is a two-piece assembly of a support member 146 and an isolation member 148. Support member 146 is made of a rigid material, for example metal, while isolation member 148 is made of a resilient and compliant material, for example an elastomer. Isolation member 148 provides resistance to transfer of heat and vibration while support member 146 provides support to isolation member 146. In order to form isolation member 148 and to retain isolation member 148 to support member 146, it is known to coat support member 146 with an adhesive and then place support member 146 into a portion of a mold cavity. Next, liquid elastomer is injected into the mold cavity where it bonds with support member 146. When the liquid elastomer is allowed to cool and solidify, the completed fuel injector isolator 118 is removed from the mold cavity. While isolation member 148 may be effective for isolating fuel injector 110, insert molding isolation member 148 to support member 146 can be difficult because the position of support member 146 must be controlled during the molding operation and flash across the insert may result from difficulty in sealing of the mold to support member 146. These issues, together with the adhesive needed to bond isolation member 148 to support member 146, increase the cost to manufacture fuel injector isolator 118 and may affect quality.
What is needed a fuel injector isolator which minimizes or eliminates one or more of the shortcomings set forth above.